The reason for the failure. Possible reasons
include:
1 = other (error which cannot be classified in
any of the types listed below).
2 = internal error occurred
3 = failed to authenticate the peer/user
4 = failed to authorize the peer/user
5 = system capacity exceeded (memory, cpu, max
users etc)
6 = peer requested to abort the session or the
setup
7 = lost peer's heartbeat
8 = local management request.